I’m not a gambling man but I suppose living in the Bay Area is a gamble in and of itself, given that the likelihood of an earthquake here of magnitude 6.7 or greater in the next 30 years is 67 percent. As our QUEST TV segment on the Hayward Fault, produced by Amy Miller, and an upcoming QUEST radio segment produced by Andrea Kissack attest, the greatest seismic risk posed to Bay Area residents is the Hayward fault, which last ruptured 150 years ago. The fact that the fault ruptures on average every 140 years, offers a sober reminder of the seismic risk that people working and residing in the East Bay face every day, including Amy and Andrea, as well as several other QUEST colleagues who reside in Berkeley and Oakland. As Mary Lou Zoback stated during the interview, a major earthquake along the Hayward fault would be economically much more catastrophic than Hurricane Katrina, coupled with the difficulty of coordinating relief services in communities like Fremont, where more than 100 languages are spoken.
So we know – or should know – the seismic risks of living in one of the most vibrant, diverse places in the U.S. Short of leaving the region, what can we do?
Well, one of the most illuminating things about working on this story for me was learning a bit about retrofitting one’s home to make it withstand the lateral and vertical forces that accompany a strong earthquake. In short, you need to build shear walls – made of reinforced plywood and shear transfer ties – and bolt them to the walls in the foundation of your house. Suprisingly, there are no official codes as to what constitutes a proper seismic retrofit of a residential unit in California, nor is there a dearth of licensed contractors who will offer quotes and purport to retrofit your home but without any standards in place, homeowners are often at a loss to evaluate the quality of the retrofit which can easily exceed ten thousand dollars, depending on the size of the home and its location. Still, homeowners can avail themselves of a few retrofit resources online, such as Plan Set A, a guideline for retrofitting one’s home that has been approved by building departments of several Bay Area municipalities such as Oakland and Hayward. Also on the Association of Bay Area Government’s web site is a set of schematics illustrating shear wall construction. If you are interested in retrofitting your home, you should get quotes from several contractors, consult your city’s building department to inquire about permits and possibly consult a structural engineer to perform a building analysis on your home.
If you’re like me, though, and don’t own a home but want to prepare for “the big one,” it’s imperative to get an earthquake survival kit. The <red Cross sells earthquake survival kits but why not make your own, provided that it has water, first aid supplies, a flashlight, food rations and other essentials for you to survive 72 hours while waiting for emergency help. If you want to make your own kit, try the USGS, the city and county of San Francisco, or helpful suggestions from the San Francisco Chronicle and LA Times.
Living in earthquake country, it pays to be vigilant. I applaud the 1868 Hayward Earthquake Alliance, a consortium of agencies that are raising awareness of the risk posed by the Hayward fault with a series of events aimed at educating the public about the importance of preparedness, including a city-wide drill in San Francisco on October 21st, the 140th anniversary of the 1868 Hayward earthquake. We may not be able to predict when exactly the next earthquake on the Hayward fault may occur but we can start planning today to mitigate its effects.
For those who aren’t familiar with the Hayward fault, check out our this link to the USGS Google Earth tour over the fault.